Hi
@Johno2009 and welcome to the forum.
![Hi :wave:](https://forums.thinkfish.co.uk/Smileys/emotions/wave.gif)
We tend to routinely use the dH German, and yours being 11.64 is very good as it is within the rage of a lot of fish, with the exception of those that like very soft water.
My water is quite hard (around 16), and I tend t0 use RO water to take some of my tanks down to around 12.
Did you check the nitrate levels on the water company site too? The lower the better, and it's always good to know what is in your tap water.
![Smiley :)](https://forums.thinkfish.co.uk/Smileys/emotions/smiley.gif)